Three towers will appear around the arena. At least one person must stand in each to prevent excessive group-wide AoE damage. When they go off, they will transform into glowing puddles with rings hovering above them. Used to dodge Barrier Shift.
Purple/Black Lightning: grants you a Lightning attunement buff.
White/Blue Ice: grants you an Ice attunement buff.
Red/Yellow Fire: grants you a fire attunement buff.
Any player with the wrong Pillars buff that attacks the boss will take heavy damage. Stand in the matching puddle to the buff that the boss gets to prevent this.
Advice and Tips
If you don't stand in a Pillar, you won't get one of the attunement buffs, meaning that you don't need to worry about Barrier Shift or attuning to the right buff.